1. Field of the Invention
The invention relates to an arrangement having an automation device, a backup device and a method for reproducing the sequence of a program provided for process control in an automation device.
2. Description of the Related Art
In the automation environment, there is often a desire to be able to largely understand the behavior of an automation device and subsequently evaluate data and the changes the automation device. For example, a user would like to test a control program created for an automation device and would like to quickly and reliably find errors that occurred during process control, in particular also errors that occurred sporadically or even only once. It is also an aim of a manufacturer or supplier of automation devices to quickly detect and eliminate errors in the firmware of the automation devices or in a system program provided for the devices. It may also be necessary to demonstrate to a user that neither the firmware nor a system program is the cause of an error that has occurred but, rather, a defective or erroneously created user or control program. In order to investigate such errors or such a behavior, trace mechanisms are provided but the these cannot be used to record all variables and the changes in the variables.
The situation may also occur in which an installation operator must subsequently verify the quality of a product produced months or years ago, for example. The operator will usually archive selected production data, for such as by using an operating and observation system. However, the archived data are not sufficient, under certain circumstances, to assess the product quality in the specific individual case. Complete comprehensibility cannot be achieved using known archiving means or measures.